Previously, we developed novel gold nanophotonic crescent moon structures with a sub-10 nm sharp edge, which can enhance local electromagnetic field at the edge area. In this project, we present a uniform array of the gold nanocrescents to generate stronger local electromagnetic field by summing up the effects of inter-particle and intra-particle electromagnetic field coupling. Stronger surface enhancement Raman scattering (SERS) signal is expected from the nanocrescent array due to the high density of the “hot spots”. The long-term goal of this project is to apply this uniform and sensitive SERS substrate to mapping the protein secretion from a single cell.